Relationship between the refractive index and absorption


by asdfghhjkl
Tags: absorption, index, refractive, relationship
asdfghhjkl
asdfghhjkl is offline
#1
Nov14-13, 06:12 AM
P: 4
Hello,

I was wondering is there a relation between the refractive index of the material and the amount of light the material absorbs (e.g. the higher n means higher absorption)? If so what is then a relation between the intensity of the light and the refractive index?

p.s. I am trying to apply this to some geological thin section observations, thus a simple explanation would be appreciated.

Thank you :)
Phys.Org News Partner Physics news on Phys.org
Physicists consider implications of recent revelations about the universe's first light
Vacuum ultraviolet lamp of the future created in Japan
Grasp of SQUIDs dynamics facilitates eavesdropping
adjacent
adjacent is online now
#2
Nov14-13, 06:34 AM
PF Gold
adjacent's Avatar
P: 848
Quote Quote by asdfghhjkl View Post
Hello,

I was wondering is there a relation between the refractive index of the material and the amount of light the material absorbs (e.g. the higher n means higher absorption)? If so what is then a relation between the intensity of the light and the refractive index?

p.s. I am trying to apply this to some geological thin section observations, thus a simple explanation would be appreciated.

Thank you :)
There is no relation between the intensity of light and the refractive index.Refractive index depends on the speed of light through the medium.It varies with wavelength too.
asdfghhjkl
asdfghhjkl is offline
#3
Nov14-13, 06:38 AM
P: 4
Ok, thank you.

adjacent
adjacent is online now
#4
Nov14-13, 06:49 AM
PF Gold
adjacent's Avatar
P: 848

Relationship between the refractive index and absorption


Quote Quote by asdfghhjkl View Post
Ok, thank you.
Please give thanks by using the "thanks" button.
DrDu
DrDu is offline
#5
Nov14-13, 07:01 AM
Sci Advisor
P: 3,375
There is a relation between absorption and refractive index which is known as Kramers Kronig relation:
http://www.rp-photonics.com/kramers_...relations.html
However, to deduce the one from the other, you need to know the absorption or refractive index ideally for all frequencies.
Andy Resnick
Andy Resnick is offline
#6
Nov14-13, 08:23 AM
Sci Advisor
P: 5,468
Quote Quote by asdfghhjkl View Post
Hello,

I was wondering is there a relation between the refractive index of the material and the amount of light the material absorbs (e.g. the higher n means higher absorption)? If so what is then a relation between the intensity of the light and the refractive index?
Echoing DrDu, absorption is often modeled by allowing the refractive index to be complex-valued (say n = η + iκ) the real part η is the 'refractive' component and the imaginary part κ the 'absorption' component. The components are not independent but related through the Kramers-Kronig relation.
Claude Bile
Claude Bile is offline
#7
Nov15-13, 07:44 AM
Sci Advisor
P: 1,465
The intensity-dependent component of the refractive index is known as the Kerr nonlinearity (real part) and saturable absorption (imaginary part).

Claude.


Register to reply

Related Discussions
dielectric constant refractive index relationship General Physics 3
Relationship between density and refractive index of a medium Classical Physics 1
Refractive index of gold? (& negative refractive index, + surface plasmon resonance?) Atomic, Solid State, Comp. Physics 3
Relationship between Refractive index and Inpedance General Physics 5
Refractive index Introductory Physics Homework 1